Enterprise Power Hybrid Active Power Filter Research And Design

In the recent years, with the development of power electronic technology, more and more nonlinear loads and devices were used in the electricity system, made the grid harmonic pollution become more and more serious, but high power quality has become increasingly demanding for users. Therefore, harmonic wave management has become a major research field and a urgent problem.This dissertation focused on the research of harmonic suppression and reactive compensation in smelter rectifying power supply system. A novel HHAPF (High-capacity Hybrid Active Power Filter) was proposed to solve the problem. And study it from the following aspects.This paper first introduces the basic principle of active power filter, current research situation and development trends, all kinds of HAPF are investigated and compared here. The High-capacity Hybrid Active Power Filter is selected. And there are detailed analysis for the system structure, work principle and mathematic model.In order to make the HHAPF work better and avoid the resonance with the impedance take place, there are detailed analysis and parameters design for it’s main components. Then there are detailed analysis of p-q computational detection method based on the instantaneous reactive power theory and improved ip-iq computational detection of harmonic detection method, and the two methods were studied comparatively. A sliding-window and iterative harmonic current detection algorithm was proposed based on DFT (Discrete Fourier Transform). The method has the characteristics that easy realization and less calculation. The simulation results show that the algorithm can effectively detect the real-time harmonic reference instruction current and has good real-time and tracing simultaneously.Finally the control strategy of active power filter was introduced in this dissertation, and according to the necessary analysis of frequency dividing control in HHAPF, and a fuzzy-PI control method based on generalized integrator presented. In this way a effective frequency dividing control method, which simplified the frequency dividing detection part in the control. In order to ensure the stability of DC voltage in active power filter, we use the PI controller to control the DC voltage. Through the simulation of MATLAB, verifies that this control algorithm has fast response time with no steady-state error characteristics, and no-error control was realized.